Kumārajīva left very little of his own writings. The only works extant are a commentary on the Vimalakīrtinirdeśa Sūtra in the form of notes probably taken down by his disciples (T. 38, No. 1775), and a collection of his correspondence with Hui-yüan (T. 45, No. 1856), often called the Ta Ch’eng ta i chang (hereafter referred to as the Correspondence). Neither text contains a discussion of the two truths as such, but in the Correspondence Kumārajīva does allude to different levels of truth, or doctrine. …

This work also contains the idea, based on the Ta Chih tu lun (The Treatise on the Great Prajñāpāramitā), that the śrāvakas follow the Four Noble Truths to realize the Buddhist path, but bodhisattvas know that the truth is One. Kumārajīva puts it this way:

The wisdom of śrāvakas is dull, therefore they must first learn this path [of advancing gradually from the stage of stream winner to Arhat] and later attain power. Since bodhisattvas understand profoundly, they have the insight that the four [noble] truths are one truth. … The śrāvakas use the four truths to understand the true aspects of reality. Bodhisattvas use the one truth to understand the true aspects of reality. The wisdom of the śrāvakas is dull so they often have a fearful mind. The wisdom of the bodhisattva is acute, so they often have a compassionate mind. Both realize the same true aspects of reality. [T. 45, 140b28-c5]

There is no mention of the two truths as such, but the idea of different levels of truth, which are ultimately one truth, is clear.

Kumārajīva also declares that:

one cannot state that form and so forth have permanence. For what reason? Because they arise from groups of causes and conditions, and perish moment by moment. Also, because they are included in the skahdha, dhātu, and āyatana, we cannot say that they are inexistent. [T. 45, 137c12-14]

This is reminiscent of Chih-i’s presentation of the threefold truth without the third aspect of the Middle: (a) Form is not permanent; it is comprised of a group of causes and conditions. This is the meaning of “emptiness,” and the content of the first aspect of Chih-i’s threefold truth concept. (b) However, this does not mean that one is affirming a nihilistic nothingness or inexistence. The forms of skahdha dhātu, and āyatana have conventional existence. This is the viewpoint of the worldly truth, and is the content of the second aspect of Chih-i’s threefold truth concept.

In China the viewpoint of emptiness (a) was identified as the supreme truth, so Chih-i utilized the concept of the Middle as a “third truth” to bring the two viewpoints (a) and (b) together into a united whole. At the time of Kumārajīva the problem had not yet taken this form. If Kumārajīva had been asked how he would harmonize his above statement with the Mādhyamika doctrine of the two truths, we may speculate that he would have said that both standpoints (a) and (b) are the conventional truth (saṃvṛtisatya) and that both of them together, or neither, are the supreme truth (paramārthasatya).

In both the Correspondence and commentary on the Vimalakīrtinirdeśa Sūtra Kumārajīva reveals himself to be an orthodox Śūnyavādin and Mādhyamikan who relies chiefly on the Pañcaviṃśati-sāhasrikā-prajn͂āpāramitā Sūtra and Ta Chih tu lun for his doctrine. In fact Robinson goes so far as to conclude that “Kumārajīva’s doctrine is the doctrine of the Great Perfection of Wisdom Treatise.”